Pick the right penstemon

Choose your variety according to your climate

Lauren Springer,

SPECIES FOR AREAS WITH HOT, DRY SUMMERS AND COLD WINTERS

BRIGHTLY COLORED FLOWERS

This group includes flashy species that insist on dry conditions and hot summers. They are cold-hardy to at least Sunset climate zone 2b (from the Sunset Western Garden Book). They are not long-lived, lasting from three to five years. The brightly colored species are favored by hummingbirds. Bloom is midseason (late spring and early summer), unless noted.

Some of the best true-blue blossoms in the plant kingdom are found in this group. All are hardy to zone 2b, most even to zone 1. They prefer dry soil, cool nights, and low humidity. They bloom for several weeks at midseason.

This group includes some of the tallest species, all native to southern Arizona, California, and Mexico. Their thick, waxy foliage adds to their appeal. They need heat to perform well and are not winter-hardy in the intermountain region. Their life span is typically three to five years. Most are favored by hummingbirds.

P. centranthifolius. Red; early to midseason. 4 to 5 feet. Long bloom season.

P. clevelandii. Rose pink; early. 2 to 3 feet.

P. parryi. Rose pink; early. 3 to 4 feet.

P. spectabilis. Indigo blue; early. 4 to 5 feet.

P. superbus. Red; early. 5 to 6 feet.

LOW-GROWING SPECIES

These species grow less than 1 foot tall and are hardy to at least zone 2b. They have attractive evergreen foliage and mounding or mat-forming habits. All bloom midseason, unless noted.

Sometimes referred to as garden penstemon or European hybrids, these showy plants were once bred mainly overseas. Best suited to coastal areas, they dislike intense heat and are not reliably cold-hardy in the interior West. As a group they are short-lived, but the darker-flowered selections tend to grow longer. They need regular water during the growing season and autumn. Typically, they grow 18 to 30 inches tall and bloom late.